What to do, and when

Twice a year, from the ground

You do not need to be on the roof to find most problems. A slow lap of the house at a low angle finds nearly all of them.

Look in the attic after heavy weather

Check after the first real weather of the season rather than at the end of it. A small stain found in autumn is a cheap repair; the same stain found in spring is not.

Keep the penetrations honest

Rubber pipe boots are the single most common source of leaks on an otherwise sound roof, and they are cheap to replace before they fail.

Clear the gutters before the wet season

Gutters full of grit are not just a drainage problem — the grit is your roof, and its presence tells you something about how far along the covering is.

Deal with growth properly

Moss and algae hold water against the surface. Treat and brush gently, or fit zinc or copper strip near the ridge. Never pressure wash an asphalt roof — it strips the granules and takes years off it in an afternoon.

Cut back anything touching the roof

Branches abrade the surface in wind and drop debris that holds moisture. Keep growth well clear of the covering, and clear of the gutters while you are at it.

In short

None of this is difficult and none of it is expensive. It is simply the difference between a roof that reaches its rated life and one that does not.